Genetics: Maternal mutations may affect lifespan

Maternally transmitted genetic mutations in the mitochondrial DNA (mtDNA) seem to shorten the lifespan of mice, a paper in Scientific Reports indicates. The findings add to a growing body of evidence that suggests maternally inherited mtDNA mutations can have life-long consequences on overall health.

Unlike most genetic material, mitochondrial DNA (mtDNA) is inherited exclusively from the mother. Mitochondrial dysfunction is thought to have an important role in the ageing process, and previous research has demonstrated that that inherited mtDNA mutations can cause premature ageing in mice. Jaime Ross and colleagues show that, in addition to causing the early onset of ageing, mtDNA mutations may reduce median longevity by around 30%. They show that mice burdened by only low levels of mtDNA mutations had a mean lifespan of 100.2 weeks, compared with 141.1 weeks for mice whose mothers lacked mtDNA mutations. Thus, these data suggest that maternally inherited mtDNA mutations can have an overall negative effect on health and lifespan.